. >>> ever since the sunday night when president obama told the world of osama bin laden's demise, curiosity about the navy s.e.a.l.s who killed him has been insatiable. now one former high level officer is pulling back a bit more of the curtain, describing what these men go through to become a s.e.a.l. >> reporter: this used to be something none of us were meant to see. much less videotape and put on television. the navy s.e.a.l.s didn't only operate in the shadows. they trained in them, too. their whole story stayed shrouded in mystery. their secret missions stayed secret to the rest of us. but when they got osama bin laden, and when they're snatching back an american cargo ship captain taken by pirates and rescuing two aid workers in somalia, then it is like the s.e.a.l.s are headline makers. add to that that some of them are writing books about s.e.a.l. adventures, even acting in a movie about the s.e.a.l. experience, which by the way, live bullets, that's what they used when they made "act of valor," and you can no longer quite call them the military unit that no one ever talked about.